A Windows Communication Foundation (WCF) solution uses two services to manage a shopping cart. Service A processes messages containing line items that total between $0 and $500. Service B processes messages containing line items that total more than $500. All messages are of equal importance to the business logic. You need to route incoming messages to the appropriate services by using WCF routing. Which two message filters should you add to the router? (Each correct answer presents part of the solution. Choose two.)（）

• A、a message filter with a priority of 100 that will forward messages that total between $0 and $500 to Service A
• B、a message filter with a priority of 0 that will forward messages that total between $0 and $500 to Service A
• C、a message filter with a priority of 0 that will forward all messages to Service B
• D、a message filter with a priority of 100 that will forward all messages to Service B